When one of the aspiring science teachers he trains enters his office, Alters wants the props to serve as a reminder of why they chose that particular field. "The important thing to remember is that science is fun," says Alters. He thinks science teachers have an almost unfair advantage over teachers in other disciplines. "We have labs, we do experiments, we have hands-on activities." History and geography teachers have to rely on textbooks and maps. Science teachers can light up a Bunsen burner to drive home their points.

Not that science teachers don't have their thorny challenges to contend with. Take evolution, for instance. According to Alters, the theory of evolution is accepted by "about 99.9% of scientists." It's a cornerstone for the entire discipline of biology. "Without a doubt, this is one of the most important topics there is," says Alters. "It's the ultimate 'where do I come from' question."

But talk to an average Joe on Main Street about evolution and he's likely to turn up his nose and say it's a load of bunk.

Polls by respected firms like Gallup are consistent on the subject -- half of all Americans don't believe in evolution. "They think the teachers have it wrong," says Alters. "They think the textbooks are wrong."

A Harvard-trained researcher, Alters has long been interested in why so many people dismiss a theory that scientists almost universally believe to be true. The reasons are often religious, Alters says, but he's discovered that they're also often the result of a profound misconception about how science operates.

Together with University of Southern California educational psychologist William B. Michael, Alters recently surveyed or interviewed 1,200 first-year students at 10 different American colleges. They discovered that among the students who disbelieved in evolution, about 45% maintained specific misconceptions about what evolutionary science is all about.

These students were likely to agree with statements such as "mutations are never beneficial to animals" or "the methods used to determine the age of fossils and rocks are not accurate." Scientists have ample evidence to prove the inaccuracy of such views.

This is an important finding, says Alters. Science teachers should never attack the religious beliefs of their students in the classroom, he maintains. But misconceptions about how science works are fair game.

"It's important not to proselytize. That would be abusing my position. What we can do is ensure that students understand the evidence that leads scientists to conclude that evolution is what happened."

Alters explores these themes in an innovative graduate course he teaches called "Evolution, Religion and Education." The course was one of a handful that recently won a worldwide competition for "outstanding courses in science and religion" organized by the Templeton Foundation, an organization interested in how the interplay between religion and science is dealt with at schools. Alters's course took home a $14,000 prize.

"We operate by unusual rules in the course," says Alters. "You can put forth or defend or attack any position you want to. But no one in the course ever knows if you actually believe in what you're arguing. That goes for me too -- students have no idea where I'm coming from. I generally play devil's advocate. If I see the students leaning in one direction, I'll argue for the other side."

Creationists end up arguing the case for evolution and vice versa. "It takes the pressure off people -- they don't dig in their heels and feel that their personal beliefs are under attack.

"The course isn't about proposing that one way of knowing the world is better than another way of knowing the world," says Alters. He's trying to instill some mutual respect into the arguments between those who believe in evolution and those who don't.

"I want my students to understand that every side has an intellectual point of view to put forth -- that's what education is all about. You have to know all the arguments -- not just the ones that support your own way of thinking. You have to understand where other people are coming from."

Alters stresses that creationists are not dummies. He points to Kurt Wise, who earned a PhD from Harvard in paleontology studying under Stephen Jay Gould, possibly the planet's most persuasive and passionate advocate of evolution. "Wise didn't believe in evolution going in, he didn't believe in it while he was studying at Harvard, he didn't believe in it when he graduated. He just didn't find the evidence compelling enough. This guy successfully completed the highest degree offered by one of the best universities in the world."

Students in Alters's course have access to a range of guest lecturers -- such as philosophy professor Mario Bunge, one of the world's most respected experts on the philosophy of science, religious studies professor Terrance Kirby and Philip Sadler, director of science education at the Harvard-Smithsonian Center for Astrophysics.

Alters joined McGill last summer. He held an interesting array of jobs before arriving at the University. As the chair of a high school science department in Southern California, Alters built a marine science program that took students whale-watching and conducted oceanographic research on Catalina and the Guam Islands. The well-equipped program (which had, among other things, a mini-submarine at its disposal) attracted the attention of Jacques Cousteau's team. Alters was also a biochemical research scientist at the Los Angeles County Museum of Natural History and the president of a science video production company.

His most unusual career shift involved a stint as a street cop in some of California's toughest neighbourhoods.

"Since the third grade, I knew that I was going to make my life in science," explains Alters. "I'd been an academic and a scientist my entire life -- a nerd, basically. I wanted to see what a whole other way of life was all about."

Alters says he wasn't suited to spending the rest of his working life as a cop. "There is very little creativity in that job. It's maintenance work -- very important maintenance work, mind you."

His time as a police officer taught him some important life lessons. "It puts everything into perspective. When I come across a problem now, I know it's not a life or death situation -- I've seen life or death situations up close."

Any other career changes in the offing? Alters says he's content to stay put at McGill. "I wanted the opportunity to teach in a different country and Quebec is perfect -- it's close enough to the U.S. that I can visit my relatives and friends, but it also offers a very unique culture that I couldn't find anywhere in the U.S. And I like the atmosphere of a university, there are so many options, so many things you can do. You're only limited by the constraints of your mind."

Still, Alters feels the lure of another life on occasion. "Every time I hear a siren, I do kind of miss being in a squad car."